In general, a flow instrument (including a flowmeter, an electrical sensor, a hydrometer, a hydraulic meter, etc.; hereinafter, referred to as a “flowmeter”), which is installed in a pipe or the like to measure flow of fluid, is a device used in houses, buildings and others to exactly measure a volume of fluid used, and such a flowmeter is mounted at a certain position in a pipe, i.e., a water and wastewater pipe, to indicate a volume of fluid (water) flowing in the pipe with numbers.
Such a flowmeter includes a calculation means that calculates a signal detected from measuring a flow rate of fluid flowing in a pipe, and a display means that visually displays the flow rate calculated in the calculation means.
Pipes are connected to both opened ends of the flowmeter, and a rotor rotating by fluid is installed in a passageway of the inside of the flowmeter, wherein an end of the rotor is formed with a magnetizable magnetic inductor, and thus, the calculation means outputs a signal detected from sensing the magnetic inductor of the rotor rotating by fluid, so as to indicate a volume of the fluid with numbers.
This electronic flowmeter is equipped with a battery for supply of a power and normally operates by the power. Further, there is a disadvantage in that since the battery equipped in the flowmeter is consumable, electric energy stored in the battery is fully exhausted as certain time lapses.
Moreover, the conventional flowmeter has a problem in that even if the battery has run out, and thus, operated abnormally, no one may know the abnormal operation of the flowmeter until he/she personally checks the flowmeter, and is inconvenient in that the battery should be replaced with new one every time it is exhausted.
Meanwhile, in this regard, Korean Utility Model Publication No. 20-0300991 (entitled: “Flowmeter”) describes a flowmeter, which measures a flow rate when fluid flows.